改善a—SiTFTLCD像素电极跳变电压方法研究

非晶硅薄膜晶体管液晶显示器（a—SiTFTLCD）中，在栅极信号由开启到关断的瞬间，由于栅源耦合电容Cgs的存在．使像素电极电压出现跳变，跳变前后像素电极电压差称为△Vp。降低△Vp一方面能减小闪烁程度，降低残像残留．同时还能最大程度地提高像素电极保持阶段的电压。防止出现因TFT漏电流过大而造成的像素电极电压衰变到所应显示灰度电压之下，从而出现显示灰阶的变化。本文从理论上分析了△Vp形成原理，介绍了两种能有效降低△Vp的方法．即多栅极电路和脉冲式存储电容。

The Investigation to Improve Kickback Voltage of Pixel Electrode of a-Si TFT LCD

At a-Si TFT LCD, when gate signal is from on state to off state ,due to the coupling capacitance Cgs of gate electrode and source electrode ,the voltage of pixel electrode takes place kickback, we name the kickback voltage as ΔVp. One side,decreasing ΔVp can decrease flicker level and image sticking ;On the other side , decreasing ΔVp can mostly improve the voltage of pixel electrode at holding stage , and avoid the change of display gray level, which is that the bigger TFT Ioff leads to the voltage of pixel electrode under the voltage of needing display gray level. The paper analyzes ΔVp forming mechanism in theory, and introduces two kinds of effective methods to decrease ΔVp ,namely MLG and pulse Cst.